'I' gets so used by them (7)

I believe the answer is:

egoists

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'them' is the definition.
I can't tell whether this defines the answer.

'i gets so used' is the wordplay.
'used' is an anagram indicator.
'i'+'gets'+'so'='igetsso'
'igetsso' with letters rearranged gives 'EGOISTS'.

'by' acts as a link.

Can you help me to learn more?

(Another definition for egoists that I've seen is " Selfish, vain types".)

I've seen this clue in The Globe and Mail.

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